Duplex or twin piston pump.



PATENTED JUNE 2, 1903.

,B. VOGBL. DUPLEXOR TWIN PISTON PUMP.

APPLICATION FILED MAR. 15, 1902.

2 SHEETS-SHEET 1.

I0 MODEL.

mils PETERS co. PnOTuu'mo" WASHINOYON. o. c.

PATENTED JUNE-2', 1903.

E. VOGEL. DUPLEX 0R TWIN PISTON PUMP.

APPLICATION FILED MAR. 15, 1902.

2 SHEETS-SHEET NOMODBL.

8 a P i a Z s z 0 mwh I 3% P P flwr 4 y F W d A f m w NITED STATES Patented. June 2, 1903.

ERNST VOGEL, OF BITTERFELD, GERMANY, ASSIGNOR TO THE FIRM OF ORTENBACII & VOGEL, OF BITTERFELD, PRUSSIA, GERMANY.

DUPLEX OR TWIN PISTON PUMP.

SPECIFICATION forming part of Letters Patent No. 730,179, dated June 2, 1903.

Application filed March 15. 1902. Serial No. 98,380. (No model.)

To all whom, it may cmwern:

Be it knownthat I, ERNST VOGEL, a citizen of the German Empire, residing at Bitterfeld, in the Kingdom of Prussia, Germany, have invented certain new and useful Improvements in or Relating to Duplex or Twin Piston Pumps; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to double acting pumps; and it consists in the novel construction and combination of the parts hereinafter fully described and claimed.

In the drawings, Figure 1 is a diagram of the pump drawn in longitudinal section with all the passages shown in a single plane and with the piston g at the left-hand end of its stroke. Fig. 2 is a diagram similar to Fig. 1, but shows the piston e at the right-hand end of its stroke. Fig. 3 is a diagram similar to Fig. 1, but shows the piston g at the righthand end of its stroke. Fig. 4 is a diagram similar to Fig. 1, but shows the piston e at the left-hand end of its stroke.

The pump consists of two working cylinders c (1, arranged side by side and provided with corresponding pistons e J. In extensions of the cylinders or casing and at the same time forming part of the passages are formed the cylinders for the piston-slides fh, which are mounted upon the respective piston-rods of their working pistons. The arrangement is such that the piston-slide f of the working piston e is situated at the opposite end to that of the piston-slide h of the working piston whereby a simple connection between the channels of the cylinders is obtained.

The space between the working piston e and the corresponding piston-slidefis in constant connection with the delivery-passage 2, and similarly the space between the working piston g and the piston-slide h is in constant connection with the suction-passage 7a. The

surface of the piston-slides is half that of the working pistons.

It is necessary that the piston of one pump remain stationary until the piston-slide of the other pump begins to open the corresponding conduit. To this end the piston-rods are positively coupled with the piston-rods of two working or driving cylinders a l), which govern each other in such a manner that one piston remains stationary in its dead position until the other piston has accomplished a certain part of its stroke. This is effected by the rods of the slide-valves of the cylinders a, b being operated by levers connected to the piston-rods of the other cylinders in such manner that a convenient lap is given to the slides. In order to smoothly effect the change of stroke, special admission-passages r 0" s s and exhaust-channels t i u u are arranged so as to provide for a certain quantity of steam or air to act as a buffer or cushion behind the piston after the pistons have passed over the exhaust-ports.

As already mentioned, Figs. 1 to 4 show the four main phases during a double stroke.

In Fig. 1 the pistons efare shown moving to the right. The piston-slide f has just opened the pressure-conduit of the cylinder (1 and the pistons g h begin to move from their dead position toward the right.

In Fig. 2 the pistons ef have reached the dead position at the end of their stroke to the right, while the piston'slide 77. has just commenced to open the pressure-conduit of the cylinder 0. The pistons efnow commence to move from right to left.

In Fig. 3 the pistons efare shown at about half-way in their return stroke to the left, while the piston-slidef is just uncovering the suction-port of cylinder d. The pistons g h are in their dead position at the right just before beginning their motion to the left.

In Fig. 4. the pistons of have reached their dead position at the left-hand end and are beginning to move to the right, as the pistonslide it has on its motion to the leftj ust opened the suction-port of the cylinder d.

When the piston-slides have no lap, as shown in the German Patent No. 83,920, the pump cannot be used to pump against a high pressure, because at the moments when the slides close the passages between the cylinders and the suction and delivery passages the water is forced back by the pressure through the very narrow port-openings.

By making the slides with lap the eificiency of the pump is increased, and it is adapted to Work against high pressures. When, however, as in the said German patent, the pistons are driven by a double crank, the slides cannot be provided with lap.

In carrying, out this invention each pumppiston is actuated independent of the other and the double crank is dispensed With.

From this it will be seen that any desired lap can be given to the piston-slide without in the least affecting the efficiency of the engine. In this manner the piston-slidesfand h can be provided with lap, which is impossible when the pump-rods are actuated by a double crank. In Fig. 1 the lapf of the piston-slide f has delayed the opening of the passage between the cylinder 61 and the delivery-passage 1' until the piston c has accomplished one-half of its stroke, and in Fig. at the lap 71/ of the valve h has delayed the opening of the passage between the suction-passage 7c and the cylinder 0 until the piston g has accomplished one-half of its stroke.

What I claim is The combination, with two pumps each provided with a piston, a piston-rod, and a piston-slide secured on the said piston-rod and provided with lap, said pumps having also suction and delivery passages in common, substantially as set forth; of a separate engine for driving each said pump-piston rod independent of the other, and valve mechanism which constrains each said engine to move its pump-piston a prearranged part of its stroke while the pump-piston pertaining to the other said engine remains stationary, substantially as set forth.

In testimony whereof I affix my signature in presence of two witnesses.

ERNST VOGEL.

WVitnesses:

ANTON DEINERT, LoUIs ZEN'rsoH. 

